This invention relates to a method and apparatus for securing vehicle service lines in desired relative positions and more particularly to mechanism and apparatus for securing brake service lines in over-the-highway trucks and tractors.
Vehicles are equipped with flexible service lines which extend between a vehicle body and/or a vehicle frame and vehicle suspension systems. In over-the-highway trucks and tractors, there typically are air lines which extend along the vehicle frame to a location near each of the wheels and two flexible lines which extend from the frame to each wheel. One of the lines is a line which is normally pressurized when the vehicle is in use to maintain socalled spring brakes or parking brakes in an off condition against the biasing of springs which automatically apply the brakes when air pressure is released. The other line is to service brakes for arresting a vehicle motion under operator control.
Heretofore there has been no truly satisfactory solution to maintaining such flexible brake lines appropriately positioned. For example, brake hose clips have been used to secure such lines in place. Such clips may cause wearing and premature failing of a secured line. In addition, no provision is made for interconnecting pairs of brake lines in desired spatial relationship.
Automatic brake systems (ABS) are frequently installed in modem over-the-highway vehicles. These systems sense wheel lock up which will cause skidding and release brake pressure momentarily to assure maximized motion arresting while wheels continue to rotate rather than skid. Desirably ABS lines like the air lines, should be maintained in desired relative positions free of abrasion causing contact with vehicle components and potential resulting breakage.
U.S. Pat. No. 5,941,483 issued Aug. 24, 1998 to Frank Baginski entitled Service Line Clamp With Cable Mount discloses a highly successful arrangement which secures service lines to frames. Neither the Baginski arrangement or the other prior arrangements has adequately solved the problem of maintaining spatial relationships between sections of service lines such as those which span between a frame and a vehicle""s wheels.
A unitary retainer for service lines to maintain such lines in desired positions and minimize wear and excessive flexing is provided. The retainer when installed maintains a pair of service lines such as brake air lines running to wheels in desired spatial relationship, thereby minimizing flexing and abrasive wear due to contact with one another and other components of a vehicle.
The retainer is a unitary molded plastic device preferably made of 6xe2x80x946 nylon. The retainer includes a central body and a spaced pair of straps secured to the body. Each of the straps has a toothed surface. The body has a pair of spaced strap receiving slots for respectively receiving end portions of the straps. Projections within the slots selectively and flexibly engage the teeth such that the straps may be fed through in tightening relationship but are retained in a service line gripping relationship by the projections.
Unlike prior toothed restrainers, the teeth of the straps of the present retainers are formed on a surface which is an outer surface when the retainer is in use. Thus, as an example, if the strap is retainingly wrapped around an air line, the strap surface engaging the line is a smooth surface. This smooth surface to air line engagement inhibits wear if there is relative motion between the straps and the lines. Moreover, since there is smooth surface to surface engagement, there are no interstices where foreign particles can collect and cause abrasive wear if there is movement of the strap relative to the line being engaged as has characterized prior art toothed strap line retention devices.
The body includes a second pair of recesses through which an independent tie may be fed, to, for example, secure ABS lines to the retainer.
A typical proposed application of the retainer of this invention is in air services lines running from an over-the-highway truck or tractor frame to wheels mounted on a rear axle. In such an application a pair of the retainers will be used. One retainer of the pair will secure the air lines together at a location about one third the distance from the frame to the wheels being served, while the second retainer will be positioned at about two thirds of the distance from the frame to the wheels.
If the over-the-highway vehicle has an ABS system, ABS electrical conductors are preferably also secured to the retainers.
Accordingly, the objects of the invention are to provide a novel and improved service line positioning system and a retainer for such a system.